Zimbra Webmail Classic UI Local File Inclusion Vulnerability
A high-severity Local File Inclusion (LFI) vulnerability has been identified in the Webmail Classic UI of Zimbra Collaboration Suite (ZCS) versions 10.0 and 10.1. The flaw, tracked as CVE-2025-68645, arises from improper handling of user-supplied request parameters in the RestFilter servlet, allowing unauthenticated remote attackers to craft requests to the /h/rest endpoint and include arbitrary files from the WebRoot directory. This vulnerability exposes internal files to attackers, potentially leading to the disclosure of sensitive information and further compromise of affected Zimbra installations.
Security researchers have highlighted the risk that this LFI vulnerability poses, as it can be exploited without authentication and may serve as a stepping stone for more advanced attacks. Organizations using Zimbra Collaboration Suite are urged to review their deployments and apply any available patches or mitigations to prevent exploitation. The vulnerability has been assigned a CVSS 3.1 score of 8.8, reflecting its high impact and ease of exploitation.
Timeline
Dec 25, 2025
Public reporting warns of unauthenticated file access risk in Zimbra
Subsequent security reporting highlighted that the Zimbra LFI issue could let unauthenticated attackers access internal files and expose sensitive information on affected servers. The coverage emphasized the urgency of patching to reduce the risk of data exposure and further exploitation.
Dec 22, 2025
CVE-2025-68645 published for Zimbra Webmail Classic UI LFI flaw
A high-severity local file inclusion vulnerability affecting Zimbra Collaboration Suite 10.0 and 10.1 was published as CVE-2025-68645. The flaw in the RestFilter servlet allows unauthenticated remote attackers to use the /h/rest endpoint to include arbitrary files from the WebRoot directory.
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